1. Field of the Invention
The present invention relates to a magnetic disk in which magnetic data are allowed to be read and written so as to reproduce and store the magnetic data, and more particularly to a magnetic disk which is configured so as to maintain cleanness of a recording plane of a disk-like magnetic data recording medium, thereby allowing data to be correctly read and written.
2. Related Art
FIG. 5 shows the structure of a prior art magnetic disk which is called a flexible disk or a floppy disk.
As shown in the figure, in the magnetic disk 1, a disk case 2 is configured by bonding a pair of upper and lower shells (or jackets) 3 to each other, and a disk-like magnetic data recording medium 4 in which data can be read and written is rotatably incorporated in the disk case 2. In the shells 3, rectangular windows 6 are formed by performing cutting in a radial direction so that a reading/writing head of a floppy disk drive (not shown) serving as a data reading/writing device is allowed to be externally contacted with a magnetic data recording plane 5 of the magnetic data recording medium 4 to read and/or write data. Disk-like liners 7 which are made of rayon or polyester are bonded to faces of the case 2 corresponding to the magnetic data recording plane 5 of the magnetic data recording medium 4, so as to be opposed to the magnetic data recording plane 5.
As shown in FIGS. 6(A) and 6(B), an infinite number of projections and depressions are formed in the surface of each of the liners 7, and the liners 7 support the front and back sides of the magnetic data recording medium 4 which is rotating, so that, while preventing the medium from being directly contacted with the inner faces 8 of the case 2, the liners clean the recording plane by wiping away dust deposited on the magnetic data recording plane 5, in positions upstream and downstream from the reading/writing head of the floppy disk drive in the rotation direction.
As shown in FIG. 5, a shutter 10 is slidably attached to the case 2 so as to open and close the windows 6. The shutter 10 is configured in the following manner. When the magnetic disk 1 is inserted into a magnetic disk slot (not shown) of the floppy disk drive, the shutter is engaged with an opening and closing device (not shown) which is incorporated in the vicinity of the slot, to perform an opening operation. At this time, the reading/writing head is contacted with the reading/writing surface of the magnetic disk 1 by a predetermined load pressure.
As described above, in the magnetic disk 1, dust on the magnetic data recording plane 5 is wiped away by contacting between the liners 7 and the magnetic data recording plane 5. However, the liners 7 have a low ability of attracting and holding dust, and, during a period when the rotation of the disk is stopped, cannot prevent dust from being deposited on the magnetic data recording plane 5.
Consequently, there arises a technical problem which is to be solved in order to efficiently attract dust deposited on a magnetic data recording plane of a magnetic data recording medium, and hold the attracted dust. It is an object of the invention to solve the technical problem.
The invention has been conducted in order to attain the object.
The invention provides a magnetic disk comprising:
a disk-like magnetic data recording medium in which data are allowed to be read and written; and
electrostatic attracting means for attracting dust by means of an electrostatic attractive force, the electrostatic attracting means being made of an electrostatic material and opposed to a magnetic data recording plane of the magnetic data recording medium.
The invention provides also a magnetic disk wherein the magnetic disk further comprises:
a disk-like magnetic data recording medium in which data are allowed to be read and written; and
a disk case which rotatably incorporates the disk-like magnetic data recording medium, and
the electrostatic attracting means is configured by liners which are made of an electrostatic material, and which are interposed between inner faces of the case and the magnetic data recording plane of the magnetic data recording medium to support front and back sides of the magnetic data recording medium, the liners attracting dust by means of an electrostatic attractive force.
The invention provides also a magnetic disk wherein the magnetic disk further comprises:
a disk-like magnetic data recording medium in which data are allowed to be read and written;
a disk case which rotatably incorporates the disk-like magnetic data recording medium; and
liners which are interposed between inner faces of the case and the magnetic data recording plane of the magnetic data recording medium to support front and back sides of the magnetic data recording medium, and
the electrostatic attracting means is configured by subliners which are made of an electrostatic material, and which are interposed between the liners and the magnetic data recording plane of the magnetic data recording medium, the subliners attracting dust by means of an electrostatic attractive force.